In the prior art ceiling lamps or stand lamps, the lamp body 10 is installed to one end of a support 11 (referring to FIG. 1). A base 12 is connected to the stand tube 13 so as to be positioned thereto. However the form of the lamp has only one type. Furthermore, the light projection area of the lamp and the illumination thereof is fixed so that it can not be adjusted based on the requirement of the users or the change of environment so as to have preferred vision and hearing effect. Thereby the prior art is necessary to be improved.